KR20190140126A - Optical member and display including the same - Google Patents

Abstract

An optical member and a display device including the same are provided. An optical member according to an embodiment is disposed on a light guide plate, the light guide plate, a low refractive index layer having a refractive index smaller than that of the light guide plate, a low refractive layer disposed between the low refractive layer and the light guide plate, and having a lower thickness than the low refractive layer. And a wavelength converting layer disposed on the refractive lower layer and the low refractive layer.

Description

Optical member and display including the same {Optical member and display including the same}

The present invention relates to an optical member and a display device including the same.

The liquid crystal display receives light from the backlight assembly and displays an image. Some backlight assemblies include a light source and a light guide plate. The light guide plate receives light from the light source and guides the light propagation direction toward the display panel. In some products, the light provided by the light source is white, and the white light is filtered by a color filter on the display panel to realize color.

Recently, in order to improve image quality such as color reproducibility of a liquid crystal display, applying a wavelength conversion film has been studied. In general, a blue light source is used as a light source, and a wavelength conversion film is disposed on the light guide plate to convert white light. Wavelength converting films include wavelength converting particles, which are generally vulnerable to moisture to protect the wavelength converting particles with a barrier film. However, the barrier film is expensive and may cause the thickness to increase. In addition, since the wavelength conversion film must be laminated on the light guide plate, a complicated assembly process may be required.

The problem to be solved by the present invention is to provide an optical member having a laminated structure with improved light transmission efficiency.

Another object of the present invention is to provide a display device including an optical member having a laminated structure with improved light transmission efficiency.

The objects of the present invention are not limited to the above-mentioned objects, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

An optical member according to an embodiment for solving the above problems is a light guide plate, a low refractive index layer disposed on the light guide plate, having a refractive index smaller than the light guide plate, disposed between the low refractive index layer and the light guide plate, the low refractive layer A low refractive index lower layer having a smaller thickness and a wavelength conversion layer disposed on the low refractive index layer.

The lower surface of the low refractive index lower layer may contact the upper surface of the light guide plate, and the upper surface of the low refractive index lower layer may contact the lower surface of the low refractive index layer.

The low refractive index lower layer may include a low refractive material having a refractive index of 1.3 to 1.7 or a high refractive material having a refractive index of 1.5 to 2.2.

The refractive index of the low refractive index lower layer may be greater than the refractive index of the low refractive index layer.

The low refractive index lower layer may include a first low refractive index lower layer disposed on the light guide plate and a second low refractive index lower layer disposed on the first low refractive index lower layer.

One of the first low refractive index lower layer and the second low refractive index lower layer may include the low refractive material, and the other may include the high refractive material.

The thickness of the first low refractive index lower layer and the thickness of the second low refractive index lower layer may be 0.2 μm or less, respectively.

The low refractive material may be SiOx, and the high refractive material may be SiNx.

The difference in refractive index between the light guide plate and the low refractive index layer may be 0.2 or more.

The low refractive index layer may include a void.

The refractive index of the low refractive layer may be 1.2 to 1.3.

The low refractive index layer may be 0.8um to 1.2um.

The optical member may further include a wavelength conversion upper layer disposed on the wavelength conversion layer.

The lower surface of the wavelength conversion upper layer may be parallel to the upper surface of the light guide plate.

The wavelength conversion upper layer may include SiOx or SiNx.

The wavelength conversion top layer may include a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer.

One of the first wavelength converting upper layer and the second wavelength converting upper layer may include a transparent organic material, and the other may include any one of SiOx and SiNx.

The first wavelength converting upper layer may include SiOx, and the second wavelength converting upper layer may include a transparent organic material.

One of the first wavelength converting upper layer and the second wavelength converting upper layer may include SiOx, and the other may include SiNx.

The wavelength conversion top layer may further include a third wavelength conversion top layer on the second wavelength conversion top layer.

The first wavelength conversion upper layer may include a transparent organic material.

One of the second wavelength converting top layer and the third wavelength converting top layer may include SiOx, and the other may include SiNx.

The light guide plate may include glass.

An upper surface of the light guide plate may be parallel to a lower surface of the low refractive layer.

According to another aspect of the present invention, an optical member includes a light guide plate, a low refractive layer disposed on the light guide plate, and having a refractive index smaller than that of the light guide plate, a wavelength conversion layer disposed on the low refractive layer, and the low refractive layer. And a low refractive index upper layer disposed on the wavelength conversion layer and having a thickness smaller than that of the low refractive index layer.

The low refractive upper layer may include a low refractive material having a refractive index of 1.3 to 1.7 or a high refractive material having a refractive index of 1.5 to 2.2.

The refractive index of the low refractive upper layer may be greater than the refractive index of the low refractive layer.

The low refractive upper layer may include a first low refractive upper layer disposed on the low refractive layer and a second low refractive upper layer disposed on the first low refractive upper layer.

One of the first low refractive index upper layer and the second low refractive index upper layer may include the low refractive material, and the other may include the high refractive material.

The thickness of the first low refractive upper layer and the thickness of the second low refractive upper layer may be 0.2 μm or less, respectively.

The low refractive material may be SiOx, and the high refractive material may be SiNx.

The optical member may further include a wavelength conversion upper layer disposed on the wavelength conversion layer.

The wavelength conversion upper layer may include SiOx or SiNx.

The wavelength conversion top layer may include a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer.

One of the first wavelength converting upper layer and the second wavelength converting upper layer may include a transparent organic material, and the other may include any one of SiOx and SiNx.

The first wavelength converting upper layer may include SiOx, and the second wavelength converting upper layer may include a transparent organic material.

The wavelength conversion top layer may further include a third wavelength conversion top layer on the second wavelength conversion top layer.

According to another aspect of the present invention, an optical member includes a light guide plate, a low refractive layer disposed on the light guide plate, and having a refractive index smaller than that of the light guide plate, a wavelength conversion layer disposed on the low refractive layer, and the low refractive index. A low refractive index lower layer disposed between the layer and the light guide plate, and a low refractive index upper layer disposed on the low refractive index layer and the wavelength conversion layer.

The low refractive index lower layer may include SiOx or SiNx, and the refractive index of the low refractive index lower layer may be greater than the refractive index of the low refractive index layer.

The low refractive index lower layer may include a first low refractive index lower layer disposed on the light guide plate and a second low refractive index lower layer disposed on the first low refractive index lower layer.

The thickness of the first low refractive index lower layer and the thickness of the second low refractive index lower layer may be 0.2 μm or less, respectively.

The low refractive upper layer may include SiOx or SiNx, and the refractive index of the low refractive upper layer may be greater than that of the low refractive layer.

The low refractive upper layer may include a first low refractive upper layer disposed on the low refractive layer and a second low refractive upper layer disposed on the first low refractive upper layer.

The thickness of the first low refractive upper layer and the thickness of the second low refractive upper layer may be 0.2 μm or less, respectively.

The wavelength converting upper layer may be further disposed on the wavelength converting layer, and the wavelength converting upper layer may include SiOx or SiNx.

The wavelength conversion top layer may include a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer.

One of the first wavelength converting upper layer and the second wavelength converting upper layer may include a transparent organic material, and the other may include any one of SiOx and SiNx.

The first wavelength converting upper layer may include SiOx, and the second wavelength converting upper layer may include a transparent organic material.

The wavelength conversion top layer may further include a third wavelength conversion top layer on the second wavelength conversion top layer.

According to an exemplary embodiment of the present invention, a display device includes a light guide plate, a low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate, a low refractive index lower layer disposed between the low refractive layer and the light guide plate; And an optical member including a wavelength conversion layer disposed on the low refractive layer, a light source disposed on at least one side of the light guide plate, and a display panel disposed on the optical member.

The low refractive index lower layer may include SiOx or SiNx, and the refractive index of the low refractive index lower layer may be greater than the refractive index of the low refractive index layer.

The low refractive index lower layer may include a first low refractive index lower layer disposed on the light guide plate and a second low refractive index lower layer disposed on the first low refractive index lower layer.

The wavelength converting upper layer may be further disposed on the wavelength converting layer, and the wavelength converting upper layer may include SiOx or SiNx.

The wavelength conversion top layer may include a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer.

The wavelength conversion top layer may further include a third wavelength conversion top layer on the second wavelength conversion top layer.

The optical member may further include a low refractive upper layer disposed between the wavelength conversion layer and the low refractive layer.

The low refractive upper layer may include SiOx or SiNx, and the refractive index of the low refractive upper layer may be greater than that of the low refractive layer.

The wavelength converting upper layer may be further disposed on the wavelength converting layer, and the wavelength converting upper layer may include SiOx or SiNx.

According to another aspect of the present invention, a display device includes: a light guide plate, a low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate, a wavelength conversion layer disposed on the low refractive layer, and the low refractive index. And an optical member including a low refractive upper layer disposed between the layer and the wavelength conversion layer, a light source disposed on at least one side of the light guide plate, and a display panel disposed above the optical member.

The low refractive upper layer may include SiOx or SiNx, and the refractive index of the low refractive upper layer may be greater than that of the low refractive layer.

The wavelength converting upper layer may be further disposed on the wavelength converting layer, and the wavelength converting upper layer may include SiOx or SiNx.

Specific details of other embodiments are included in the detailed description and drawings.

The optical member according to the exemplary embodiment may simultaneously perform the light guide function and the wavelength conversion function, and may improve the light transmission efficiency by the stack structure of materials having different refractive indices. An optical member according to an embodiment has a relatively thin thickness and may maximize light transmission efficiency to improve optical characteristics of the display device.

Effects according to the embodiments are not limited by the contents illustrated above, more various effects are included in the present specification.

1 is a perspective view of an optical member and a light source according to an embodiment.
FIG. 2 is a cross-sectional view taken along the line II-II 'of FIG. 1.
3 and 4 are cross-sectional views of a low refractive layer according to various embodiments.
FIG. 5 is a graph showing transmittance change according to the thickness of the SiNx layer on the light emitting plate and the laminated case of the wavelength conversion lower layer.
FIG. 6 is a table illustrating a lamination structure and a thickness for securing a maximum transmittance for each lamination case of a wavelength conversion lower layer.
7-14 are cross-sectional views of a wavelength converting underlayer in accordance with various embodiments.
FIG. 15 is a graph showing transmittance change according to the thickness of the stacked case of the wavelength converting upper layer and the SiNx thickness of the upper part of the wavelength converting layer.
FIG. 16 is a table illustrating a lamination structure and a thickness for securing a maximum transmittance for each lamination case of a wavelength conversion upper layer.
17 through 20 are cross-sectional views of a wavelength converting upper layer according to various embodiments.
21 to 23 are cross-sectional views of optical members according to various embodiments.
24 is a cross-sectional view of a display device according to an exemplary embodiment.
25 is a cross-sectional view of a display device according to another exemplary embodiment.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims.

References to elements or layers as "on" of another element or layer include all instances where another layer or other element is interposed over or in the middle of another element. Like reference numerals refer to like elements throughout.

Although the first, second, etc. are used to describe various components, these components are of course not limited by these terms. These terms are only used to distinguish one component from another. Therefore, of course, the first component mentioned below may be a second component within the technical spirit of the present invention.

Hereinafter, exemplary embodiments will be described with reference to the accompanying drawings.

1 is a perspective view of an optical member and a light source according to an embodiment. FIG. 2 is a cross-sectional view taken along the line II-II 'of FIG. 1.

1 and 2, the optical member 100 includes a light guide plate 10, a wavelength conversion bottom layer 70 disposed on the light guide plate, a wavelength conversion layer 50 disposed on the wavelength conversion bottom layer 70, and a wavelength. The wavelength conversion upper layer 60 may be disposed on the conversion layer 50. The wavelength converting underlayer 70 may include a low refractive index lower layer 20, a low refractive index layer 30 disposed on the low refractive index lower layer 20, and a low refractive index upper layer 40 disposed on the low refractive index layer 30. Can be.

The light guide plate 10 serves to guide a light propagation path. The light guide plate 10 may have a generally polygonal pillar shape. The planar shape of the light guide plate 10 may be rectangular, but is not limited thereto. In an exemplary embodiment, the light guide plate 10 may have a hexagonal column shape having a rectangular planar shape and may include four side surfaces 10s and 10s1, 10s2, 10s3, and 10s4. In this specification and the accompanying drawings, it is indicated as “10s1”, “10s2”, “10s3”, and “10s4” when it is necessary to distinguish each of the four sides, but as “10s” for simply referring to one side. Mark it.

In one embodiment, the top surface 10a and the bottom surface 10b of the light guide plate 10 are located on one plane, respectively, and the plane where the top surface 10a is located and the plane where the bottom surface 10b are located are substantially parallel to the light guide plate. 10 may have a uniform thickness as a whole. However, the present invention is not limited thereto, and the upper surface 10a or the lower surface 10b may be formed of a plurality of planes, or the plane on which the upper surface 10a is positioned may intersect with the plane on which the lower surface 10b is positioned. For example, the thickness may become thinner from one side (eg, the light incident surface) to the other side (eg, the light facing surface) facing the same, such as a wedge-shaped light guide plate. In addition, up to a specific point, the lower surface 10b is inclined upwardly toward the other side (for example, the light receiving surface) toward the other side (for example, the light receiving surface), and the thickness thereof decreases, and then the upper and lower surfaces 10b have a flat shape. It may be formed.

In one application of the optical member 100, the light source 400 may be disposed adjacent to at least one side 10s of the light guide plate 10. In the drawing, a case in which a plurality of LED light sources 410 mounted on the printed circuit board 420 is disposed on the side surface 10s1 positioned at one long side of the light guide plate 10 is not limited thereto. For example, the plurality of LED light sources 410 may be disposed adjacent to both side surfaces 10s1 and 10s3 of both long sides, or may be disposed adjacent to side surfaces 10s2 and 10s4 of one short side or both short sides. In the embodiment of FIG. 1, the side surface 10s1 of one long side of the light guide plate 10 in which the light source 400 is disposed adjacent is a light incident surface on which light of the light source 400 is directly incident (10s1 for convenience of description in the drawing). And the side surface 10s3 of the other long side opposite thereto becomes a light facing surface (denoted as '10s3' for convenience of description in the drawing).

The light guide plate 10 may include an inorganic material. For example, the light guide plate 10 may be made of glass, but is not limited thereto.

An optical interface may be formed at the surfaces where the layers 20, 30, 40, 50, and 60 of the optical member 100 meet each other. The optical member 100 may include a plurality of optical interfaces 30a, 30b, 50a and 50b. Each optical interface 30a, 30b, 50a, 50b may be substantially parallel to the top surface 10a of the light guide plate 10.

The wavelength conversion lower layer 70 is disposed on the upper surface 10a of the light guide plate 10. The wavelength conversion lower layer 70 may include a low refractive index layer 30, a low refractive index lower layer 20, and a low refractive index upper layer 40. The wavelength conversion lower layer 70 may be directly formed on the upper surface 10a of the light guide plate to contact the upper surface 10a of the light guide plate. The wavelength conversion lower layer 70 is interposed between the light guide plate 10 and the wavelength conversion layer 50 to help total reflection of the optical member 100.

In more detail, in order for the light guide to be efficiently guided from the light receiving surface 10s1 to the light facing surface 10s3 by the light guide plate 10, it is preferable that the internal reflection is effectively performed in the light guide plate 10. One of the conditions under which total internal reflection may occur in the light guide plate 10 is that the refractive index of the light guide plate 10 is larger than the refractive index of a medium forming an optical interface therewith. As the refractive index of the medium forming the optical interface with the light guide plate 10 is lower, the total reflection critical angle becomes smaller, thereby allowing more internal total reflection.

Referring to the case where the light guide plate 10 is made of glass having a refractive index of about 1.5, the lower surface 10b of the light guide plate 10 is exposed to an air layer having a refractive index of about 1 and forms an optical interface therewith. Can be.

On the other hand, since the other optical functional layers are laminated and integrated on the upper surface 10a of the light guide plate 10, it is difficult to achieve a total reflection more sufficiently than that of the lower surface 10b. For example, when a material layer having a refractive index of 1.5 or more is stacked on the top surface 10a of the light guide plate 10, total reflection may not be performed on the top surface 10a of the light guide plate 10. In addition, when a layer of material having a refractive index smaller than that of the light guide plate 10, for example, about 1.49, is stacked on the top surface 10a of the light guide plate 10, total internal reflection may occur on the top surface 10a of the light guide plate 10. In this case, the critical angle is too large for sufficient total reflection. The wavelength conversion layer 50 laminated on the upper surface 10a of the light guide plate 10 generally has a refractive index of about 1.5. When the wavelength conversion layer 50 is directly laminated on the upper surface 10a of the light guide plate 10, the light guide plate In the upper surface 10a of (10), it is hard to make sufficient total reflection.

The low refractive index layer 30 interposed between the light guide plate 10 and the wavelength conversion layer 50 to interface with the upper surface 10a of the light guide plate 10 has a lower refractive index than the light guide plate 10 and thus has a low refractive index layer 30. The total reflection is to be made at the bottom (30b). In addition, the low refractive index layer 30 has a lower refractive index than the wavelength conversion layer 50, which is a material layer disposed thereon, so that the wavelength conversion layer 50 is directly disposed on the upper surface 10a of the light guide plate 10. More total reflection can be achieved.

When the low refractive index lower layer 20 is disposed on the light guide plate 10, total reflection may occur due to a difference in refractive index even at the interface between the light guide plate 10 and the low refractive index lower layer 20, but at an angle smaller than the total reflection critical angle at the interface. The incident light may be transmitted through the low refractive index lower layer 20. Reflection and / or refraction occur again at the interface of the low refractive index lower layer 20 and the low refractive index layer 30. When the refractive index of the low refractive index layer 30 is smaller than the refractive index of the low refractive index lower layer 20, total reflection is also performed at the interface. Can be done. When the optical member 100 includes the low refractive index lower layer 20, the low refractive index lower layer 20 is interposed between the light guide plate 10 and the low refractive index layer 30, but finally determining the critical angle of the total reflection is the light guide plate. This is a difference between the refractive indices of (10) and the low refractive index layer (30). As the refractive index of the low refractive index layer 30 is smaller, the difference in the refractive index becomes larger, so that the total reflection critical angle becomes smaller, thereby allowing more total internal reflection.

The wavelength conversion lower layer 70 interposed between the light guide plate 10 and the wavelength conversion layer 50 to interface with the upper surface 10a of the light guide plate 10 may include a low refractive index layer 30. The low refractive index layer 30 has a lower refractive index than the light guide plate 10 so that total reflection is made at the bottom surface 30b of the low refractive index layer 30. In addition, the low refractive index layer 30 has a lower refractive index than the wavelength conversion layer 50, which is a material layer disposed thereon, so that the wavelength conversion layer 50 is directly disposed on the upper surface 10a of the light guide plate 10. More total reflection can be achieved.

The difference between the refractive index of the light guide plate 10 and the refractive index of the low refractive layer 30 may be 0.2 or more. When the refractive index of the low refractive layer 30 is 0.2 or less than the refractive index of the light guide plate 10, sufficient total reflection may be achieved through the lower surface 30b of the low refractive layer 30. The upper limit of the difference between the refractive index of the light guide plate 10 and the refractive index of the low refractive index layer 30 is not limited. However, the refractive index of the light guide plate 10 and the low refractive index layer 30 may be 1 or less. The refractive index of the low refractive layer 30 may be in the range of 1.2 to 1.4. In general, the solid phase medium increases exponentially with the manufacturing cost as the refractive index approaches 1. If the refractive index of the low refractive index layer 30 is 1.2 or more, excessive increase in manufacturing cost can be prevented. In addition, it is advantageous that the refractive index of the low refractive index layer 30 is 1.4 or less to sufficiently reduce the total reflection critical angle of the upper surface 10a of the light guide plate 10. In an exemplary embodiment, a low refractive index layer 30 having a refractive index of about 1.25 may be applied.

In order to exhibit the low refractive index described above, the low refractive index layer 30 may include voids. The voids may be made of a vacuum or filled with an air layer, gas or the like. The void space can be defined by particles or matrices. Reference is made to FIGS. 3 and 4 for further details.

3 and 4 are cross-sectional views of a low refractive layer according to various embodiments.

In one embodiment, as shown in FIG. 3, the low refractive layer 30 may include a plurality of particles PT, a matrix MX and a void VD surrounding the particles PT and connected in one whole. have. The particle PT may be a filler that controls the refractive index and the mechanical strength of the low refractive index layer 30.

In the low refractive layer 30, particles PT may be distributed and disposed in the plurality of matrices MX, and the matrix MX may be partially spread to form voids VD. For example, a plurality of particles PT and a matrix MX are mixed in a solvent, and then dried and / or cured to evaporate the solvent, and voids VD may be formed between the matrix MX. .

In another embodiment, low refractive index layer 30 may include matrix MX and void VD without particles, as shown in FIG. 4. For example, the low refractive layer 30 may include a matrix MX, which is entirely connected to one another, such as a foamed resin, and a plurality of voids VD disposed therein.

As shown in FIGS. 3 and 4, when the low refractive index layer 30 includes voids VD, the total refractive index of the low refractive index layer 30 is determined by the refractive index of the particle PT / matrix MX and the void ( It may have a value between the refractive index of VD). As described above, when the void VD is filled with a vacuum having a refractive index of 1 or an air layer having a refractive index of approximately 1, a gas, or the like, even if a material of 1.4 or more is used as the particle PT / matrix MX, the low refractive layer 30 ) May have a value of 1.4 or less, such as about 1.25. In an exemplary embodiment, the particles PT may be made of an inorganic material such as SiO ₂ , Fe ₂ O ₃ , MgF _2, and the matrix MX may be made of an organic material such as polysiloxane, but other organic materials. It may also be made of minerals.

Referring again to FIGS. 1 and 2, the thickness of the low refractive layer 30 may be 0.4 μm to 2 μm. When the thickness of the low refractive layer 30 is 0.4 µm or more, which is the visible light wavelength range, an effective optical interface may be achieved, and total reflection according to Snell's law may be well performed on the bottom surface 30b of the low refractive layer 30. If the low refractive index layer 30 is too thick, the thickness of the optical member 100 may be reversed, the material cost may increase, and the brightness of the optical member 100 may be disadvantageous. It may be formed to a thickness of. In an exemplary embodiment, the thickness of the low refractive layer 30 may be about 1 μm.

The low refractive index lower layer 20 may be disposed between the light guide plate 10 and the low refractive index layer 30. The low refractive index lower layer 20 may be directly formed on the upper surface of the light guide plate 10 to contact the upper surface of the light guide plate 10. In addition, the bottom surface of the low refractive layer 30 may be in contact with the bottom surface of the low refractive layer 30. The low refractive index lower layer 20 may be interposed between the light guide plate 10 and the low refractive index layer 30. The low refractive index lower layer 20 may have a larger refractive index than the low refractive index layer 30. The low refractive index lower layer 20 may be a single layer structure made of any one of a low refractive material and a high refractive material. In addition, the low refractive index lower layer 20 may have a multilayer structure in which low refractive materials and high refractive materials are alternately stacked. The refractive index of the low refractive material may be 1.3 to 1.7. The refractive index of the high refractive material may be 1.5 to 2.2. In one embodiment, the low refractive material may be SiOx, and the high refractive material may be SiNx. However, the low refractive material and the high refractive material are not limited thereto, and may be various materials satisfying the refractive index.

According to the stacking material and the stacking thickness of the low refractive index lower layer 20, the influence of the constructive interference or the destructive interference of the light changes, so that the light transmittance is changed. That is, light transmittance may be controlled by adjusting the stacking material and the stacking thickness of the low refractive index lower layer 20. In addition, when the low refractive index lower layer 20 includes an inorganic film, the low refractive index lower layer 20 may serve as a protective film that prevents moisture / oxygen from penetrating into the low refractive index layer 30.

The low refractive index upper layer 40 may be disposed between the low refractive index layer 30 and the wavelength conversion layer 50. The low refractive index upper layer 40 may be formed directly on the upper surface of the low refractive index layer 30 to contact the upper surface of the low refractive index layer 30. In addition, the bottom surface of the wavelength conversion layer 50 may be in contact. The low refractive index upper layer 40 may be interposed between the low refractive index layer 30 and the wavelength conversion layer 50. The low refractive index upper layer 40 may have a larger refractive index than the low refractive index layer 30. The low refractive index upper layer 40 helps total reflection to occur in the direction of the wavelength conversion layer 50 on the upper surface of the low refractive index layer 30. The low refractive index upper layer 40 may have a single layer structure made of any one of a low refractive material and a high refractive material. In addition, the low refractive index upper layer 40 may have a multilayer structure in which low refractive materials and high refractive materials are alternately stacked. The refractive index of the low refractive material, such as the low refractive index lower layer 20 may be 1.2 to 1.7. The refractive index of the high refractive material may be 1.5 to 2.2. In one embodiment, the low refractive material may be SiOx, and the high refractive material may be SiNx. However, the low refractive material and the high refractive material are not limited thereto, and may be various materials satisfying the refractive index.

According to the stacking material and the stacking thickness of the low refractive upper layer 40, the influence of the constructive or destructive interference of the light changes, so that the light transmittance is changed. That is, the light transmittance may be controlled by adjusting the stacking material and the stacking thickness of the low refractive upper layer 40. In addition, the low refractive upper layer 40 may improve the optical efficiency of the optical member 100. When the light passing through the low refractive layer 30 enters the wavelength conversion layer 50 and meets scattered scattered particles, the wavelength is changed and scattered. Some of the scattered light may travel in the direction of the light guide plate 10 again. When the low refractive index upper layer 40 has a higher refractive index than the low refractive index layer 30, total reflection is made at the interface thereof, and the upper surface of the low refractive index layer 40 may be reflected upward, thereby increasing optical efficiency such as brightness of the display device.

The low refractive index upper layer 40 may completely overlap the low refractive index layer 30 to prevent penetration of moisture and / or oxygen into the low refractive index layer 30. That is, the low refractive index upper layer 40 can prevent the deformation of the low refractive index layer 30, and may increase the hardness to bring structural stability. In addition, the low refractive index upper layer 40 including the inorganic layer may serve to prevent moisture and / or oxygen from penetrating into the upper wavelength converting layer 50 and the lower low refractive index layer 30.

The wavelength conversion lower layer 70 may be formed by a method such as deposition and coating. The wavelength conversion lower layer 70 may be formed on the light guide plate 10 in the order of the low refractive index lower layer 20, the low refractive index layer 30, and the low refractive index upper layer 40. In one embodiment, the low refractive index lower layer 20 and the low refractive index upper layer 40 may be formed using a chemical vapor deposition method as an inorganic film containing an inorganic material. The low refractive layer 30 may be formed by using a coating method as an organic film including an organic material. The coating method may include slit coating, spin coating, roll coating, spray coating, inkjet, and the like, but is not limited thereto, and various other lamination methods may be applied.

The wavelength converting layer 50 is disposed on the wavelength converting underlayer 70. In an embodiment, when the wavelength conversion lower layer 70 includes the low refractive upper layer 40, the wavelength conversion layer 50 may be disposed on an upper surface of the low refractive upper layer 40. In another embodiment, when the wavelength conversion lower layer 70 does not include the low refractive index upper layer 40, the wavelength conversion layer 50 may be disposed on the top surface of the low refractive index layer 30. The wavelength conversion layer 50 may include a binder layer and wavelength conversion particles dispersed in the binder layer. The wavelength conversion layer 50 may further include scattering particles dispersed in the binder layer in addition to the wavelength conversion particles.

The binder layer is a medium in which the wavelength conversion particles are dispersed, and may be made of various resin compositions that may generally be referred to as binders. However, the present invention is not limited thereto and may be referred to as a binder layer regardless of its name, additional functions, materials, and the like, as long as the medium capable of dispersing the wavelength converting particles and / or the scattering particles.

The wavelength conversion particles are particles that convert wavelengths of incident light, and may be, for example, quantum dots (QDs), fluorescent materials, or phosphorescent materials. The quantum dot, an example of a wavelength conversion particle, is a material having a crystal structure of several nanometers in size, composed of hundreds to thousands of atoms, and because of its small size, the energy band gap is reduced. The increasing quantum confinement effect is shown. When light of a wavelength having a higher energy than the band gap is incident on the quantum dot, the quantum dot is excited by absorbing the light and falls to the ground state while emitting light of a specific wavelength. Light of the emitted wavelength has a value corresponding to the band gap. The quantum dots can control the light emission characteristics due to the quantum confinement effect by adjusting the size and composition thereof.

Quantum dots are, for example, group II-VI compounds, group II-V compounds, group III-VI compounds, group III-V compounds, group IV-VI compounds, group I-III-VI compounds, group II-IV-VI At least one of a compound and a II-IV-V compound.

The quantum dot may include a core and a shell overcoating the core. The core is not limited thereto, but for example, CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InP, InAs, InSb, SiC, Ca, It may be at least one of Se, In, P, Fe, Pt, Ni, Co, Al, Ag, Au, Cu, FePt, Fe2O3, Fe3O4, Si, and Ge. The shell is not limited thereto, for example, ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, HgTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, GaSe, InN, It may include at least one of InP, InAs, InSb, TlN, TlP, TlAs, TlSb, PbS, PbSe, and PbTe.

The wavelength converting particle may include a plurality of wavelength converting particles for converting incident light into different wavelengths. For example, the wavelength converting particles may include first wavelength converting particles converting incident light having a specific wavelength into a first wavelength and emitting the second wavelength converting particles converting and emitting a second wavelength. In an exemplary embodiment, the light emitted from the light source 400 and incident on the wavelength conversion particle may be light of a blue wavelength, the first wavelength may be a green wavelength, and the second wavelength may be a red wavelength. For example, the blue wavelength may be a wavelength having a peak at 420 to 470 nm, the green wavelength may be a wavelength having a peak at 520 nm to 570 nm, and the red wavelength may be a wavelength having a peak at 620 nm to 670 nm. However, blue, green, and red wavelengths are not limited to the above examples, and should be understood to include all wavelength ranges that can be recognized as blue, green, and red in the art.

In the exemplary embodiment, blue light incident on the wavelength converting layer 50 passes through the wavelength converting layer 50, and a part of the blue light is incident on the first wavelength converting particle to be converted into a green wavelength and emitted. The light may be incident on the two wavelength converting particles, converted into red wavelengths, and may be emitted without being incident on the first and second wavelength converting particles. Therefore, the light passing through the wavelength conversion layer 50 includes all of light of blue wavelength, light of green wavelength, and light of red wavelength. By properly adjusting the ratio of the light of different wavelengths emitted, it is possible to display white light or output light of different colors. The light converted in the wavelength conversion layer 50 is concentrated within a specific wavelength of a narrow range, and has a sharp spectrum having a narrow half width. Therefore, when colors of the spectrum are filtered by color filters to implement colors, color reproducibility may be improved.

Unlike the above exemplary embodiment, the incident light is light having a short wavelength such as ultraviolet light, and three kinds of wavelength converting particles converting the light into blue, green, and red wavelengths may be disposed in the wavelength converting layer 50 to emit white light. have.

The wavelength conversion layer 50 may further include scattering particles. The scattering particles are non-quantum dot particles, and may be particles having no wavelength conversion function. The scattering particles scatter the incident light so that more incident light can be incident on the wavelength converting particle side. In addition, the scattering particles may serve to uniformly control the emission angle of light for each wavelength. Specifically, when some incident light is incident on the wavelength conversion particle and then the wavelength is converted and emitted, the emission direction has random scattering characteristics. If there is no scattering particles in the wavelength conversion layer 50, the green and red wavelengths emitted after the wavelength-converting particle collide have scattering emission characteristics, but the blue wavelengths emitted without the collision of the wavelength-converting particles do not have scattering emission characteristics and are emitted. Depending on the angle, the emission of the blue / green / red wavelengths will be different. Scattering particles can similarly control the emission angle of light for each wavelength by providing scattering emission characteristics with respect to blue wavelengths emitted without colliding with the wavelength conversion particles. As the scattering particles, TiO 2, SiO 2, or the like may be used.

The wavelength conversion layer 50 may be thicker than the low refractive layer 30. The thickness of the wavelength conversion layer may be about 10 to 50㎛. In an exemplary embodiment, the thickness of the wavelength conversion layer 50 may be about 10 μm.

The wavelength conversion layer 50 may be formed by a coating method or the like. For example, the wavelength conversion layer 50 may be formed by slit coating, drying, and curing the wavelength conversion composition on the light guide plate 10 on which the wavelength conversion lower layer is formed. However, the present invention is not limited thereto, and various other lamination methods may be applied.

The wavelength conversion upper layer 60 may be disposed on the wavelength conversion layer 50. The wavelength converting upper layer 60 may be a passivation layer that prevents penetration of moisture and / or oxygen (hereinafter referred to as 'moisture / oxygen'). The wavelength conversion upper layer 60 may include a plurality of laminated films. Each laminated film may include an inorganic film or an organic film. The wavelength conversion upper layer 60 may include at least one inorganic layer. That is, the wavelength conversion upper layer 60 may be formed of a single film of an inorganic film, a plurality of inorganic films, or a laminated film of an organic film and an inorganic film.

Each laminated film may comprise a high refractive material, a low refractive material and / or a transparent organic material. The wavelength conversion upper layer 60 may be a single layer film made of a low refractive material, a high refractive material, or a transparent organic material, and may be a multilayer film in which materials having different refractive indices are stacked. In one embodiment, the high and low refractive materials are silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, and silicon oxynitride. Can be. In one embodiment, the high refractive material may be SiNx (silicon nitride), and the low refractive material may be SiOx (silicon oxide). The transparent organic material may be a silicone resin, an acrylic resin, an epoxy resin, or the like.

The wavelength conversion upper layer 60 may completely overlap the wavelength conversion layer 50 and cover the top surface of the wavelength conversion layer 50. In one embodiment, the wavelength conversion upper layer 60 may cover only the top surface of the wavelength conversion layer 50, but in another embodiment, the wavelength conversion upper layer 60 may further extend outward to extend the side and wavelength of the wavelength conversion layer 50. It can cover up to the side of the transformation lower layer 70.

The wavelength conversion upper layer 60 may have a thickness of 0.1 μm to 5 μm. In an embodiment, when the wavelength conversion upper layer 60 does not include an organic layer, the thickness of the wavelength conversion upper layer 60 may be 0.15 μm to 0.5 μm. In another embodiment, when the wavelength conversion upper layer 60 includes an organic layer, the thickness of the wavelength conversion upper layer 60 may be 1 μm to 5 μm. The thickness of the wavelength conversion upper layer 60 may be smaller than the wavelength conversion layer 50. When the thickness of the wavelength conversion upper layer 60 is 0.1 µm or more, a significant moisture / oxygen penetration prevention function can be exhibited. It is advantageous from the viewpoint of thinning and transmittance that the thickness of the wavelength conversion upper layer 60 is 2 μm or less. However, the thickness of the wavelength conversion upper layer 60 is not limited thereto, and the wavelength conversion upper layer 60 may be disposed in various thicknesses. According to the refractive index and the thickness of the laminated material of the wavelength conversion upper layer 60, the amount of light extracted to the upper part, that is, the transmittance may be affected. Detailed description thereof will be described later.

The wavelength conversion upper layer 60 may be formed by a method such as coating and deposition. For example, the inorganic film including the inorganic material may be formed on the light guide plate 10 in which the wavelength conversion lower layer 70 and the wavelength conversion layer 50 are sequentially formed by using a chemical vapor deposition method. The organic layer including the organic material may be formed on the light guide plate by using a coating method. However, the present invention is not limited thereto, and various other lamination methods may be applied.

As described above, the optical member 100 may simultaneously perform the light guide function and the wavelength conversion function. The optical member 100 may include a wavelength converting lower layer 70 and a wavelength converting upper layer 60. The wavelength conversion lower layer 70 may include a low refractive index layer 30, a low refractive index lower layer 20, and a low refractive index upper layer 40. The low refractive index lower layer 20 and the low refractive index upper layer 40 may be formed of a material larger than the refractive index of the low refractive index layer 30. The low refractive index lower layer 20 and the low refractive index upper layer 40 may improve the light transmittance since the influence due to constructive or destructive interference of light incident on the optical member is changed. The wavelength conversion upper layer 60 may include a layer made of at least one of a high refractive material and a low refractive material. In addition, the wavelength conversion upper layer 60 may be a multilayer film further comprising a transparent organic material. The wavelength conversion upper layer 60 completely covers the wavelength conversion layer to prevent the penetration of moisture / oxygen. In addition, the wavelength conversion upper layer 60 may improve the optical efficiency by allowing the light transmitted through the wavelength conversion layer to be effectively emitted to the outside of the optical member 100.

In addition, the wavelength conversion upper layer 60 disposed on the wavelength conversion layer 50 of the optical member 100 may lower the manufacturing cost and reduce the thickness than the wavelength conversion film provided as a separate film. In one example, the wavelength conversion film is attached to the upper and lower barrier film of the wavelength conversion layer 50, the barrier film is not only expensive, but also thick to more than 100㎛ thickness, the total thickness of the wavelength conversion film reaches about 270㎛. On the other hand, in the optical member 100 according to the present exemplary embodiment, the entire thickness of the optical member 100 except for the light guide plate 10 may be maintained at a level of about 12 μm to 13 μm, thereby reducing the thickness of the display device employing the light guide plate 10. In addition, the optical member 100 can omit an expensive barrier film, so that the manufacturing unit cost can be managed at a lower level than the wavelength conversion film.

Hereinafter, the lamination structure and thickness of a wavelength conversion underlayer for obtaining maximum light transmittance in a wavelength conversion underlayer are demonstrated. When light passes through media with different indices of refraction, reflection and refraction of the light occur at the point where the media with different indices of refraction meet. If the refractive index and thickness of the medium are known, the Fresnel equations for the reflection and refraction of light can be used to derive the transmittance of the laminated structure. That is, a simulation may be performed to derive a transmittance according to the laminated structure and the thickness of the wavelength conversion lower layer.

FIG. 5 is a graph showing transmittance change according to the thickness of the SiNx layer on the light emitting plate and the laminated case of the wavelength conversion lower layer. FIG. 6 is a table illustrating a lamination structure and a thickness for securing a maximum transmittance for each lamination case of a wavelength conversion lower layer.

5A illustrates conditions for performing a simulation. In FIG. 5 (a), a case in which the low refractive index lower layer and the low refractive index upper layer have two layers will be described as an example. In the case where the low refractive index lower layer and the low refractive index upper layer are omitted or have only one layer, the thickness of the corresponding layer may be It is expressed as 0 μm.

2 and 5 (a), the wavelength conversion lower layer 70 is stacked on the light guide plate 10 in the order of the low refractive index lower layer 20, the low refractive index layer 30, and the low refractive index upper layer 40. . The wavelength conversion lower layer 70 may be interposed between the light guide plate 10 and the wavelength conversion layer 50. The low refractive index lower layer 20 and the low refractive index upper layer 40 may each include up to two layers.

The thickness of each layer under simulation conditions is selected in the range of 0 μm to 0.2 μm. The thickness of 0 mu m means that the layer is not included as described above. Under the simulation conditions, the thickness of the low refractive layer 30 is set to 1 µm. The layer included in the low refractive index lower layer 20 and the low refractive index upper layer 40 may be formed of a high refractive material and a low refractive material. In one embodiment, the high refractive material may be SiNx (silicon nitride), and the low refractive material may be SiOx (silicon oxide). Hereinafter, it will be described that the high refractive material is SiNx and the low refractive material is SiOx. The layer comprising the high refractive material and the layer comprising the low refractive material may be alternately stacked. The refractive index of the high refractive material and the low refractive material may be greater than the refractive index of the low refractive layer. The conditions for obtaining the light transmittance of the wavelength conversion lower layer 70 may be divided into four according to the stacked structure.

Case 1 of the wavelength converting lower layer includes a low refractive index lower layer 20 stacked in order of a low refractive material and a high refractive index material on the light guide plate, and a low refractive index upper layer 40 stacked in the order of a high refractive index material and a low refractive index material on the low refractive index layer. do.

Case 2 of the wavelength conversion lower layer includes a low refractive index lower layer 20 stacked in order of a high refractive index material and a low refractive index material on a light guide plate, and a low refractive index upper layer 40 stacked in order of a high refractive index material and a low refractive index material on the low refractive index layer. do.

Case 3 of the wavelength conversion lower layer includes a low refractive index lower layer 20 stacked in order of a high refractive material and a low refractive index material on the light guide plate, and a low refractive index upper layer 40 stacked in a low refractive material and then a high refractive index material on the low refractive layer. do.

Case 4 of the wavelength conversion lower layer includes a low refractive index lower layer 20 stacked in order of a low refractive material and a high refractive index material on the light guide plate, and a low refractive index upper layer 40 that is stacked in order of a low refractive index material and a high refractive index material on the low refractive index layer. do.

FIG. 5B is a graph showing a change in transmittance according to stacking conditions according to the thickness of SiNx of the low refractive index lower layer disposed on the light guide plate in Case 1. FIG. 5 (b) is an example of a simulation result, and the transmittance of the wavelength conversion lower layer having a stacked structure of another case may be obtained in the same manner as in FIG. 5 (b). Here, the transmittance refers to the ratio of blue light emitted through the wavelength conversion layer to blue light incident through the light source and emitted to the outside. SiNx on the graph of FIG. 5 (b) refers to a high refractive material and SiOx refers to a low refractive material.

2 and 5 (b), the wavelength conversion lower layer 70 on which the simulation of FIG. 5 (b) is performed has the structure of Case 1 described above. The wavelength conversion lower layer 70 of Case 1 includes a low refractive index lower layer 20 stacked in the order of SiNx, SiOx and a low refractive index upper layer 40 stacked in the order of SiNx, SiOx. SiNx of the low refractive index lower layer 20 corresponds to the thickness of SiNx corresponding to the X-axis on the graph of FIG. 5 (b). That is, in the graph, SiNx is a variable value, and the thicknesses of SiOx of the low refractive index lower layer 20 and SiNx and SiOx of the low refractive upper layer 40 except for SiNx of the low refractive index lower layer 20 have a specified value. FIG. 5 (b) shows three graphs (G1, G1) showing changes in transmittance according to the thickness of SiNx of the low refractive lower layer 20 when the SiOx thickness of the low refractive lower layer 20 is 0.06 μm, 0.08 μm, and 0.2 μm G2 and G3) are shown. At this time, the thickness of the SiNx and SiOx of the low refractive upper layer 40 is 0 占 퐉, respectively, and represents the case where the wavelength conversion lower layer 70 does not include the low refractive upper layer 40.

G1 is a graph showing the change in transmittance when the thickness of SiOx of the low refractive index lower layer 20 is 0.06 µm. G2 is a graph showing the change in transmittance when the thickness of SiOx of the low refractive index lower layer 20 is 0.08 μm. G3 is a graph showing a change in transmittance when the thickness of SiOx of the low refractive index lower layer 20 is 0.2 µm. G1 has a maximum transmittance when the thickness of the SiNx of the low refractive index lower layer 20 is about 0.1 mu m. G2 has a maximum transmittance when the thickness of the SiNx of the low refractive index lower layer 20 is about 0.02 μm or about 0.14 μm. G3 has a maximum transmittance when the thickness of the SiNx of the low refractive index lower layer 20 is about 0.1 mu m. That is, when the lamination structure such as the lamination order and lamination thickness is changed, the transmittance is also changed. Through this, the maximum transmittance at each lamination condition can be confirmed, and accordingly, each lamination condition having the maximum transmittance can be determined.

FIG. 6 is a table illustrating a lamination structure and a thickness for securing a maximum blue light transmittance for each lamination case of a wavelength conversion lower layer. 6 shows three result values with high transmittance for each laminated case. 1.5T Glass means 1.5mm thick LGP. The low refractive index layer is 1 µm and the wavelength conversion layer is a simulation result for the case of 10 µm. In FIG. 6, SiOx is an example of a low refractive material, and SiNx is an example of a high refractive material.

Referring to FIGS. 2 and 6, result 3 of Case 1 is a result value according to G1 described with reference to FIG. 5B. Result 3 of Case 1 includes a low refractive index lower layer 20 in which SiNx 0.1 μm and SiOx 0.06 μm are sequentially stacked on the light guide plate, and the SiNx and SiOx of the low refractive upper layer 40 are 0 μm, that is, the wavelength conversion bottom layer 70 ) Represents the transmittance of the wavelength conversion lower layer 70 that does not include the low refractive upper layer 40. The wavelength converting underlayer 70 of result 3 has a blue light transmittance of 81.3%. As such, when the maximum blue light transmittance of each case is obtained, all four cases may have a maximum transmittance of about 81.4%. The stacked structure of the wavelength conversion underlayer according to various embodiments will be described in detail with reference to FIGS. 7 to 14.

7-14 are cross-sectional views of a wavelength converting underlayer in accordance with various embodiments. 7 to 14 illustrate that each of the components of the wavelength conversion underlayers 71, 72, 73, 74, 75, 76, 77, and 78 may be arranged in various ways. The wavelength converting underlayers 71, 72, 73, 74, 75, 76, 77, and 78 include a low refractive index layer 30, wherein the low refractive bottom layer (20 in FIG. 2) or the low refractive top layer (FIG. 2). '40' may further include. In some embodiments the wavelength conversion underlayer does not include a low refractive index underlayer or a low refractive index upper layer. However, the wavelength conversion underlayers 71, 72, 73, 74, 75, 76, 77, and 78 have a low refractive index lower layer ('20 'in FIG. 2) and a low refractive index upper layer ( And at least one layer of '40' of FIG. 2. The low refractive index lower layer (20 'of FIG. 2) and the low refractive index upper layer (40' of FIG. 2) may be a single layer structure, and may have a multilayer structure in which a high refractive material and a low refractive material are alternately stacked. Hereinafter, SiNx will be taken as an example of a high refractive material and SiOx will be described as an example of a low refractive material. However, the high refractive material and the low refractive material are not limited thereto.

7 illustrates that the low refractive index lower layer 21 and the low refractive index upper layer 41 of the wavelength conversion lower layer 71 have a single layer structure. The wavelength conversion lower layer 71 of FIG. 7 has a structure corresponding to result 2 of Case 2 of FIG. 6. That is, in the wavelength conversion lower layer 71 of FIG. 7, the low refractive index lower layer 21 is a single layer made of a high refractive material, and the low refractive upper layer 41 is a single layer made of a low refractive material. In one embodiment, the low refractive index lower layer 21 is made of SiNx and has a thickness of 0.06 μm. The low refractive index upper layer 41 is made of SiO x and has a thickness of 0.1 μm. In one embodiment, the blue light transmittance of the wavelength conversion underlayer 71 is 81.3%.

FIG. 8 illustrates that the low refractive index lower layers 22a and 22b of the wavelength conversion lower layer 72 are alternately stacked with materials having different refractive indices, and the low refractive upper layer 42 has a single layer structure. The wavelength conversion lower layer 72 of FIG. 8 has a structure corresponding to result 1 and result 2 of Case 1 of FIG. 6. That is, in the wavelength conversion underlayer 72 of FIG. 8, the low refractive index underlayers 22a and 22b may be formed of a multilayer including a first low refractive index underlayer 22a and a second low refractive index underlayer 22b having different refractive indices. The low refractive index upper layer 42 may be formed of a single layer of low refractive index material. The refractive index of the first low refractive index lower layer 22a may be greater than the refractive index of the second low refractive index lower layer 22b. The second low refractive index lower layer 22b may include the same material as the low refractive upper layer 42. In one embodiment, the first low refractive index lower layer 22a is made of SiNx and has a thickness of 0.02 μm. The second low refractive index lower layer 22b is made of SiOx and has a thickness of 0.06 μm. The low refractive upper layer 42 is made of SiOx, which is a low refractive material, and has a thickness of 0.04 μm. Accordingly, the blue light transmittance of the wavelength conversion underlayer 72 is 81.4%. The wavelength converting underlayer 72 according to another embodiment is laminated with the same material as the wavelength converting underlayer 72 of one embodiment, and the thickness of each layer is different. The thickness of the first low refractive index lower layer 22a is 0.02 μm. The thickness of the second low refractive index lower layer 22b is 0.08 mu m. The thickness of the low refractive upper layer 42 is 0.14 mu m. Accordingly, the blue light transmittance of the wavelength conversion underlayer 72 is 81.4%.

9 illustrates that the low refractive index lower layers 23a and 23b of the wavelength conversion lower layer 73 are alternately stacked with materials having different refractive indices, and the low refractive upper layer 43 has a single layer structure. The wavelength conversion lower layer 73 of FIG. 9 has a structure corresponding to result 1 and result 3 of Case 2 of FIG. 6. That is, in the wavelength conversion lower layer 73 of FIG. 9, the low refractive index lower layers 23a and 23b may be formed of a multilayer including a first low refractive index lower layer 23a and a second low refractive index lower layer 23b having different refractive indices. The low refractive upper layer 43 may be formed of a single layer of low refractive material. 9 includes the same number of layers as in FIG. 8, but the refractive index of the first low refractive index lower layer 23a may be smaller than the refractive index of the second low refractive index lower layer 23b in the embodiment of FIG. 9. In addition, the first low refractive index lower layer 23a may include the same material as the low refractive upper layer 43. In one embodiment, the first low refractive index lower layer 23a is made of SiOx and has a thickness of 0.06 μm. The second low refractive index lower layer 23b is made of SiNx and has a thickness of 0.08 μm. The low refractive top layer 43 is made of SiO x and has a thickness of 0.02 μm. Accordingly, the blue light transmittance of the wavelength conversion lower layer 73 is 81.4%. The wavelength converting underlayer 73 according to another embodiment is laminated with the same material as the wavelength converting underlayer 73 of one embodiment, and the thickness of each layer is different. The thickness of the first low refractive index lower layer 23a is 0.04 μm. The thickness of the second low refractive index lower layer 23b is 0.08 mu m. The thickness of the low refractive upper layer 43 is 0.02 mu m. Accordingly, the blue light transmittance of the wavelength conversion lower layer 73 is 81.3%.

FIG. 10 illustrates a wavelength converting underlayer 74 that does not include a low refractive underlayer, and wherein the low refractive top layers 44a and 44b are multilayered. The wavelength conversion lower layer 74 of FIG. 10 has a structure corresponding to result 3 of Case 4 of FIG. 6. That is, in the wavelength conversion lower layer 74 of FIG. 10, the low refractive index lower layer does not have a thickness of 0 μm, and the low refractive upper layers 44a and 44b have the first low refractive index upper layer 44a and the second low refractive index different from each other. It may be formed of a multilayer including the refractive upper layer 44b. The refractive index of the first low refractive upper layer 44a may be smaller than the refractive index of the second low refractive upper layer 44b. In one embodiment, the first low refractive index upper layer 44a is made of SiOx and has a thickness of 0.06 μm. The second low refractive index upper layer 44b is made of SiNx and has a thickness of 0.1 μm. Accordingly, the blue light transmittance of the wavelength conversion lower layer 74 is 81.3%.

FIG. 11 illustrates that the low refractive index lower layer 25 of the wavelength conversion lower layer 75 has a single layer structure, and the low refractive upper layers 45a and 45b have a multilayer structure in which materials having different refractive indices are alternately stacked. The wavelength conversion lower layer 75 of FIG. 11 has a structure corresponding to result 1 of Case 3 of FIG. 6. That is, in the wavelength conversion lower layer 75 of FIG. 11, the low refractive index lower layer 25 is a single layer structure including a high refractive material, and the low refractive upper layers 45a and 45b may include a first low refractive upper layer 45a and different refractive indices. It may be formed of a multilayer including a second low refractive index upper layer 45b. The refractive index of the first low refractive upper layer 45a may be smaller than the refractive index of the second low refractive upper layer 45b. The low refractive index lower layer 25 may be made of the same material as the second low refractive upper layer 45b. In one embodiment, the low refractive index lower layer 25 is made of SiNx and has a thickness of 0.02 μm. The first low refractive index upper layer 45a is made of SiOx and has a thickness of 0.06 μm. The second low refractive index upper layer 45b is made of SiNx and has a thickness of 0.04 μm. Accordingly, the blue light transmittance of the wavelength conversion lower layer 75 is 81.4%.

12 illustrates that the low refractive index lower layer 26 of the wavelength conversion lower layer 76 has a single layer structure, and the low refractive upper layers 46a and 46b have a multilayer structure in which materials having different refractive indices are alternately stacked. The wavelength conversion lower layer 76 of FIG. 12 has a structure corresponding to result 1 and result 2 of Case 4 of FIG. 6. That is, in the wavelength conversion lower layer 76 of FIG. 12, the low refractive index lower layer 26 is a single layer structure including a high refractive material, and the low refractive upper layers 46a and 46b may include the first low refractive upper layer 46a having different refractive indices and It may be made of a multilayer including a second low refractive index upper layer 46b. The refractive index of the first low refractive upper layer 46a may be smaller than the refractive index of the second low refractive upper layer 46b. Although the embodiment of FIG. 12 includes the same number of layers as FIG. 11, in the embodiment of FIG. 11, the low refractive index lower layer 26 may be made of a low refractive material. In addition, the low refractive index lower layer 26 may be made of the same material as the first low refractive index upper layer 46a. In one embodiment, the low refractive index lower layer 26 is made of SiO x and has a thickness of 0.06 μm. The first low refractive index upper layer 46a is made of SiOx and has a thickness of 0.08 μm. The second low refractive index upper layer 46b is made of SiNx and has a thickness of 0.02 μm. Accordingly, the blue light transmittance of the wavelength conversion underlayer 76 is 81.4%. The wavelength converting underlayer 76 according to another embodiment is laminated with the same material as the wavelength converting underlayer 76 of the exemplary embodiment, and the thickness of each layer is different. The low refractive index lower layer 26 is 0.04 mu m. The thickness of the first low refractive index upper layer 46a is 0.08 μm. The thickness of the second low refractive upper layer 46b is 0.02 μm. Accordingly, the blue light transmittance of the wavelength conversion underlayer 76 is 81.3%.

FIG. 13 illustrates that the low refractive index lower layers 27a and 27b and the low refractive upper layers 47a and 47b of the wavelength conversion lower layer 77 have a multilayer structure in which materials having different refractive indices are alternately stacked. The wavelength conversion lower layer 77 of FIG. 13 has a structure corresponding to result 2 and result 3 of Case 3 of FIG. 6. That is, in the wavelength conversion underlayer 77 of FIG. 13, the low refractive index underlayers 27a and 27b are made of a multilayer including a first low refractive index underlayer 27a and a second low refractive index underlayer 27b having different refractive indices, The low refractive upper layers 47a and 47b may be formed of a multilayer including a first low refractive upper layer 47a and a second low refractive upper layer 47b having different refractive indices. The refractive index of the first low refractive index lower layer 27a may be greater than the refractive index of the second low refractive index lower layer 27b. The refractive index of the first low refractive upper layer 47a may be smaller than the refractive index of the second low refractive upper layer 47b. In addition, the first low refractive index lower layer 27a may be made of the same material as the second low refractive index upper layer 47b, and the second low refractive index lower layer 27b may be made of the same material as the first low refractive index upper layer 47a. have. In one embodiment, the first low refractive index lower layer 27a is made of SiNx and has a thickness of 0.02 μm. The second low refractive index lower layer 27b is made of SiOx and has a thickness of 0.02 μm. The first low refractive index upper layer 47a is made of SiOx and has a thickness of 0.04 μm. The second low refractive index upper layer 47b is made of SiNx and has a thickness of 0.06 μm. Accordingly, the blue light transmittance of the wavelength conversion lower layer 77 is 81.4%. The wavelength converting underlayer 77 according to another embodiment is laminated with the same material as the wavelength converting underlayer 77 of one embodiment and has a different thickness of each layer. The thickness of the first low refractive index lower layer 27a is 0.02 μm. The thickness of the second low refractive upper layer 47b is 0.04 μm. The thickness of the first low refractive index upper layer 47a is 0.02 μm. The thickness of the second low refractive upper layer 47b is 0.08 mu m. Accordingly, the blue light transmittance of the wavelength conversion lower layer 77 is 81.4%.

FIG. 14 illustrates a wavelength converting underlayer 78 that does not include a low refractive upper layer, as opposed to FIG. 10, and wherein the low refractive lower layers 28a and 28b are multilayered. The wavelength conversion lower layer 78 of FIG. 14 has a structure corresponding to result 3 of Case 1 of FIG. 6. That is, in the wavelength conversion lower layer 78 of FIG. 14, the low refractive upper layer does not have a thickness of 0 μm, and the low refractive lower layers 28a and 28b have the first low refractive index lower layer 28a and the second low refractive index different from each other. It may be formed of a multilayer including the refractive lower layer 28b. The refractive index of the first low refractive index lower layer 28a may be greater than the refractive index of the second low refractive index lower layer 28b. In one embodiment, the first low refractive index lower layer 28a is made of SiNx and has a thickness of 0.1 μm. The second low refractive index lower layer 28b is made of SiOx and has a thickness of 0.06 μm. Accordingly, the blue light transmittance of the wavelength conversion underlayer 78 is 81.3%.

FIG. 15 is a graph illustrating transmittance change according to the thickness of the stacked case of the wavelength conversion top layer and the SiNx thickness on the top of the wavelength conversion layer. FIG. 16 is a table illustrating a lamination structure and a thickness for securing a maximum transmittance for each lamination case of a wavelength conversion upper layer.

2 and 15, FIG. 15A illustrates a condition for performing a simulation. The wavelength conversion upper layer 60 may be disposed on the wavelength conversion layer 50. The wavelength conversion upper layer 60 may include a high refractive material, a low refractive material, and a transparent organic material. In one embodiment, the high refractive material may be SiNx (silicon nitride), and the low refractive material may be SiOx (silicon oxide). Hereinafter, it will be described that the high refractive material is SiNx and the low refractive material is SiOx. The transparent organic material may be a silicone resin, an acrylic resin, an epoxy resin, or the like. Each layer comprising a high refractive material and a low refractive material may have a thickness of 0 μm to 0.2 μm. The layer comprising the transparent organic material may have a thickness of 0 μm to 5 μm. A thickness of 0 mu m means that the layer is not included. Although six conditions can be classified according to the laminated structure of the layer including the high refractive material, the low refractive material, and the transparent organic material, three conditions showing a substantially high light transmittance will be described.

Case 1 of the wavelength conversion upper layer 60 may include a structure stacked on the wavelength conversion layer 50 in order of layers including a high refractive material, a low refractive material, and a transparent organic material.

Case 2 of the wavelength conversion upper layer 60 may include a structure in which a high refractive material and a transparent organic material are stacked on the wavelength conversion layer 50 in a layer order including a low refractive material.

Case 3 of the wavelength conversion upper layer 60 may include a structure in which a layer including a transparent organic material, a high refractive material, and a low refractive material is stacked on the wavelength conversion layer 50.

FIG. 15B is a graph showing a change in transmittance according to the thickness of SiNx disposed on the wavelength conversion layer 50 in Case 2. FIG. 15 (b) is an example of a simulation result, and the transmittance of the wavelength conversion upper layer 60 having a stacked structure of another case may be obtained in the same manner as in FIG. 15 (b). Here, the transmittance refers to a ratio of white light transmitted through the wavelength conversion upper layer 60 to white light incident through the wavelength conversion layer 50 and emitted to the outside. In the graph of FIG. 15B, SiNx refers to a high refractive material and SiOx refers to a low refractive material.

Referring to FIG. 15B, it can be seen that the transmittance also changes as the thickness of SiNx of the wavelength conversion upper layer 60 changes. When the thickness of the SiNx changes, the influence of the constructive or destructive interference of the light changes, so that the light transmittance is changed. As the thickness of SiNx increases due to light absorption by the material, the maximum light transmittance value tends to decrease. The wavelength conversion upper layer 60 according to Case 2 has a maximum transmittance when the thickness of SiNx is about 0.1 μm. As such, the maximum transmittance in each stacking condition may be obtained by changing the stacking structure such as the stacking order and stacking thickness of the wavelength conversion upper layer 60 according to Cases 1 to 3.

FIG. 16 is a table illustrating a lamination structure and a thickness for securing a maximum transmittance for each lamination case of a wavelength conversion upper layer. FIG. 16 shows three result values with high transmittance for each laminated case. In FIG. 16, SiNx is an example of a high refractive material and SiOx is an example of a low refractive material. OC refers to a transparent organic material. When the maximum light transmittance for each case is obtained, the wavelength conversion upper layer 60 may have a maximum light transmittance of 87.5% to 88.2%. A stacked structure of the wavelength conversion upper layer 60 according to various embodiments will be described in detail with reference to FIGS. 17 to 20.

17 through 20 are cross-sectional views of wavelength converting upper layers 61, 62, 63, and 64 according to various embodiments. 17 to 20 illustrate that each of the components of the wavelength conversion upper layer 61, 62, 63, 64 may be arranged in various ways. The wavelength converting top layer 61, 62, 63, 64 includes at least two or more of a high refractive material, a low refractive material and a transparent organic material to effectively transmit light and prevent moisture / oxygen from penetrating into the wavelength converting layer. It may be a multilayer structure in which layers are stacked.

FIG. 17 shows a wavelength converting upper layer disposed on the wavelength converting layer 50, and the wavelength converting upper layers 61a and 61b each have a multilayer structure including a first wavelength converting upper layer 61a and a second wavelength converting upper layer 61b. Illustrate that. The wavelength conversion upper layers 61a and 61b of FIG. 17 have a structure corresponding to result 1 to result 3 of Case 1 of FIG. 16. That is, the wavelength conversion upper layers 61a and 61b of FIG. 17 do not include a high refractive material, and may be formed of a multilayer including a first wavelength conversion upper layer 61a and a second wavelength conversion upper layer 61b having different refractive indices. . The refractive index of the first wavelength converting upper layer 61a may be greater than the refractive index of the second wavelength converting upper layer 61b. In one embodiment, the first wavelength conversion upper layer 61a is made of SiOx and has a thickness of 0.1 μm. The second wavelength conversion upper layer 61b is made of a transparent organic material and has a thickness of 2 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 61a and 61b is 87.9%. The wavelength converting upper layers 61a and 61b according to another embodiment are stacked with the same material as the wavelength converting upper layer of the exemplary embodiment, and the thickness of each layer is different. The thickness of the first wavelength conversion upper layer 61a is 0.1 μm. The thickness of the second wavelength conversion upper layer 61b is 3.5 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 61a and 61b is 87.7%. According to another embodiment, the wavelength conversion upper layers 61a and 61b may be stacked with the same material as the wavelength conversion upper layer of one embodiment, and may have different thicknesses. The thickness of the first wavelength conversion upper layer 61a is 0.1 μm. The thickness of the second wavelength conversion upper layer 61b is 4.5 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 61a and 61b is 87.5%.

18 shows a wavelength conversion upper layer 62a, 62b disposed on the wavelength conversion layer 50, and the wavelength conversion upper layer is a multilayer structure including a first wavelength conversion upper layer 62a and a second wavelength conversion upper layer 62b. Illustrate that. The wavelength conversion upper layers 62a and 62b of FIG. 18 have a structure corresponding to result 1 to result 3 of Case 2 of FIG. 16. That is, the wavelength conversion upper layers 62a and 62b of FIG. 18 may not include a transparent organic material, and may be formed of a multilayer including a first wavelength conversion upper layer 62a and a second wavelength conversion upper layer 62b having different refractive indices. have. The refractive index of the first wavelength converting upper layer 62a may be greater than the refractive index of the second wavelength converting upper layer 62b. In one embodiment, the first wavelength converting upper layer 62a is made of SiNx and has a thickness of 0.1 μm. The second wavelength conversion upper layer 62b is made of SiOx and has a thickness of 0.05 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 62a and 62b is 88.2%. The wavelength converting upper layers 62a and 62b according to another embodiment are stacked with the same material as the wavelength converting upper layer of the exemplary embodiment, and the thickness of each layer is different. The thickness of the first wavelength conversion upper layer 62a is 0.1 μm. The thickness of the second wavelength conversion upper layer 62b is 0.2 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 62a and 62b is 87.9%. In another embodiment, the wavelength conversion upper layers 62a and 62b may be stacked with the same material as the wavelength conversion upper layer of one embodiment, and may have different thicknesses. The thickness of the first wavelength conversion upper layer 62a is 0.1 μm. The thickness of the second wavelength conversion upper layer 62b is 0.35 mu m. Accordingly, the white light transmittance of the wavelength conversion upper layers 62a and 62b is 87.7%.

19 shows the wavelength converting upper layers 63a and 63b disposed on the wavelength converting layer 50, and the wavelength converting upper layers 63a and 63b form the first wavelength converting upper layer 63a and the second wavelength converting upper layer 63b. It demonstrates that it is a multilayered structure containing. The wavelength conversion upper layers 63a and 63b of FIG. 19 have a structure corresponding to result 1 of Case 3 of FIG. 16. That is, the wavelength conversion upper layer of FIG. 17 does not include a low refractive material, and may be formed of a multilayer including a first wavelength conversion upper layer 63a and a second wavelength conversion upper layer 63b having different refractive indices. The refractive index of the first wavelength converting upper layer 63a may be smaller than the refractive index of the second wavelength converting upper layer 63b. In one embodiment, the first wavelength conversion upper layer 63a is made of a transparent organic material and has a thickness of 1 μm. The second wavelength conversion upper layer 63b is made of SiNx and has a thickness of 0.05 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 63a and 63b is 88.2%.

20 shows wavelength converting top layers 64a, 64b, and 64c disposed on the wavelength converting layer 50, and wavelength converting top layers 64a, 64b, and 64c comprise first wavelength converting top layers 64a and second wavelength converting top layers. It illustrates that it is a multilayer structure including 64b and the 3rd wavelength conversion upper layer 64c. The wavelength conversion upper layers 64a, 64b, and 64c of FIG. 20 have a structure corresponding to result 2 to result 3 of Case 3 of FIG. 16. That is, the wavelength conversion upper layer 64a, 64b, 64c of FIG. 20 includes a first wavelength conversion upper layer 64a, a second wavelength conversion upper layer 64b, and a third wavelength conversion upper layer 64c having different refractive indices. Can be made. The refractive index of the first wavelength converting upper layer 64a may be the smallest, and the refractive index of the second wavelength converting upper layer 64b may be the largest. The refractive index of the third wavelength converting upper layer 64c may be greater than the refractive index of the first wavelength converting upper layer 64a and less than the refractive index of the second wavelength converting upper layer 64b. In one embodiment, the first wavelength conversion upper layer 64a is made of a transparent organic material and has a thickness of 1 μm. The second wavelength converting top layer 64b is made of SiNx and has a thickness of 0.05 μm. The third wavelength conversion upper layer 64c is made of SiOx and has a thickness of 0.05 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 64a, 64b, and 64c is 88.2%. The wavelength converting top layers 64a, 64b, and 64c according to another embodiment are stacked with the same material as the wavelength converting top layer of the exemplary embodiment, and have different thicknesses of each layer. The thickness of the first wavelength converting upper layer 64a is 1 μm. The thickness of the second wavelength conversion upper layer 64b is 0.05 μm. The thickness of the third wavelength conversion upper layer 64c is 0.3 μm. Accordingly, the white light transmittance of the wavelength conversion upper layers 64a, 64b, and 64c is 88.2%.

21 to 23 are cross-sectional views of optical members according to various embodiments. 21 to 23 illustrate that the above-described wavelength converting lower layer 70 and the wavelength converting upper layer 60 may be variously combined. Eight wavelength converting underlayers 71, 72, 73, 74, 75, 76, 77, and 78 structures described with reference to FIGS. 7 through 14 and four wavelength converting upper layers 61, 62, described with reference to FIGS. 17 through 20. In the case of combining the structures 63 and 64, the optical members 101, 102, and 103 according to 32 various embodiments may be obtained. However, the stacked structure of the optical member is not limited thereto, and may include more various stacked structures. In the optical member according to various embodiments, the wavelength conversion underlayers 71, 72, 73, 74, 75, 76, 77, and 78 described with reference to FIGS. 7 through 14 do not include the low refractive index underlayer 20. (74), the wavelength conversion bottom layer 78 that does not include the low refractive index top layer 40, and the wavelength conversion bottom layer 71, 72, 73, 75, 76, and 77 that include both the low refractive bottom layer and the low refractive top layer. Can be. The wavelength converting upper layer 60 may be four wavelength converting upper layers 61, 62, 63, and 64 described with reference to FIGS. 17 to 20.

The final light transmittance of the optical member 100 may be obtained by multiplying the blue light transmittance of the wavelength conversion lower layer 70 by the white light transmittance of the wavelength conversion upper layer 60.

Referring to FIG. 21, an optical member 101 according to an embodiment may include a wavelength converting lower layer 70 and a wavelength converting upper layer 60a. The wavelength conversion lower layer 70 may include the low refractive index layer 30 and the low refractive index upper layer 40a, and may not include the low refractive index lower layer. The wavelength conversion underlayer 70 may be the wavelength conversion underlayer 74 described with reference to FIG. 10. That is, the low refractive upper layer 40a may be a wavelength conversion lower layer 70 having a multi-layered structure without including the low refractive lower layer. The wavelength conversion upper layer 60a may have a multilayer structure in which a layer including an inorganic material or an organic material is stacked.

Referring to FIG. 22, an optical member 102 according to another embodiment may include a wavelength converting lower layer 70 and a wavelength converting upper layer 60b. The wavelength conversion lower layer 70 may include the low refractive index lower layer 20b and the low refractive index layer 30, and may not include the low refractive index upper layer. The wavelength conversion underlayer 70 may be the wavelength conversion underlayer 78 described with reference to FIG. 14. That is, the low refractive lower layer 20b may not include the low refractive upper layer, and may be the wavelength conversion lower layer 70 having a multilayer structure. The wavelength conversion upper layer 60b may have a multilayer structure in which a layer including an inorganic material or an organic material is stacked.

Referring to FIG. 23, an optical member 103 according to another embodiment may include a wavelength converting lower layer 70 and a wavelength converting upper layer 60c. The wavelength conversion lower layer 70 may include a low refractive index lower layer 20c, a low refractive index layer 30, and a low refractive index upper layer 40c. The wavelength converting underlayer 70 may include the wavelength converting underlayers 71, 72, and the wavelength converting underlayers 70 according to the exemplary embodiment except for the wavelength converting underlayers 74 and 78 of FIGS. 10 and 14. 73, 75, 76, 77). That is, the wavelength conversion underlayer 70 may include a low refractive index lower layer 20c having a single layer structure or a multilayer structure and a low refractive upper layer 40c having a single layer structure or a multilayer structure. The wavelength conversion upper layer 60c may have a multilayer structure in which a layer including an inorganic material or an organic material is stacked.

24 is a cross-sectional view of a display device according to an exemplary embodiment.

Referring to FIG. 24, the display apparatus 1000 includes a light source 400, an optical member 100 disposed on an emission path of the light source, and a display panel 300 disposed above the optical member.

The optical member may be applied to all of the optical members according to the above-described embodiments. 24 illustrates a case where the optical member 100 of FIG. 2 is applied.

The light source 400 is disposed on one side of the optical member 100. The light source 400 may be disposed adjacent to the light incident surface 10s1 of the light guide plate 10 of the optical member 100. The light source 400 may include a plurality of point light sources or linear light sources. The point light source may be a light emitting diode (LED) light source 410. The plurality of LED light sources 410 may be mounted on the printed circuit board 420. The LED light source 410 may emit light having a blue wavelength.

As illustrated in FIG. 24, the LED light source 410 may be a top emitting LED that emits light to the top surface. In this case, the printed circuit board 420 may be disposed on the sidewall 520 of the housing 500.

Blue wavelength light emitted from the LED light source 410 is incident on the light guide plate 10 of the optical member 100. The light guide plate 10 of the optical member 100 guides light and emits the light through the upper surface 10a or the lower surface 10b of the light guide plate 10. The wavelength conversion layer 50 of the optical member 100 converts a part of light having a blue wavelength incident from the light guide plate 10 into another wavelength, for example, a green wavelength and a red wavelength. The converted green wavelength and the red wavelength light are emitted upward along with the unconverted blue wavelength and provided to the display panel 300.

The scattering pattern 80 may be disposed on the bottom surface 10b of the light guide plate 10. The scattering pattern 80 serves to emit the light to the outside of the light guide plate 10 by changing the propagation angle of the light traveling in total reflection inside the light guide plate 10.

In one embodiment, the scattering pattern 80 may be provided in a separate layer or pattern. For example, a pattern layer including a protruding pattern and / or a concave groove pattern may be formed on the lower surface 10b of the light guide plate 10, or a printing pattern may be formed to function as the scattering pattern 80.

In another embodiment, the scattering pattern 80 may be formed in the shape of the surface of the light guide plate 10 itself. For example, concave grooves may be formed in the lower surface 10b of the light guide plate 10 to function as the scattering pattern 80.

The batch density of the scattering pattern 80 may vary depending on the region. For example, the area adjacent to the light incident surface 10s1 rich in the amount of light advancing relatively decreases the placement density, and the area adjacent to the light surface 10s3 where the amount of light advancing relatively small can increase the placement density.

The display device 1000 may further include a reflective member 90 disposed under the optical member 100. The reflective member 90 may include a reflective film or a reflective coating layer. The reflective member 90 reflects light emitted from the lower surface 10b of the light guide plate 10 of the optical member 100 to enter the light guide plate 10 again.

The display panel 300 is disposed above the optical member 100. The display panel 300 receives light from the optical member 100 to display a screen. As such, examples of the light-receiving display panel which receives the light to display the screen include a liquid crystal display panel and an electrophoretic panel. Hereinafter, an example of a liquid crystal display panel is used as the display panel, but the present invention is not limited thereto and other various light-receiving display panels may be applied.

The display panel 300 includes a first substrate 310, a second substrate 320 facing the first substrate 310, and a liquid crystal layer disposed between the first substrate 310 and the second substrate 320. May include). The first substrate 310 and the second substrate 320 overlap each other. In one embodiment, one substrate may be larger than the other substrate to protrude further outward. In the drawing, the case where the second substrate 320 positioned above is larger and protrudes from the side where the light source 400 is disposed is illustrated. The protruding region of the second substrate 320 may provide a space in which the driving chip or the external circuit board is mounted. Unlike the illustrated example, the first substrate 310 positioned below may be larger than the second substrate 320 to protrude outward. In the display panel 300, a region where the first substrate 310 and the second substrate 320 overlap except the protruding region may be substantially aligned with the side surface 10s of the light guide plate 10 of the optical member 100. have.

The optical member 100 may be coupled to the display panel 300 through an intermodule coupling member 610. The intermodule coupling member 610 may be formed in a planar rectangular frame shape. The intermodule coupling member 610 may be positioned at an edge portion of the display panel 300 and the optical member 100, respectively.

In one embodiment, the bottom surface of the intermodule coupling member 610 is disposed on the top surface of the wavelength converting upper layer 60 of the optical member 100. The lower surface of the intermodule coupling member 610 may be disposed on the wavelength conversion upper layer 60 so as to overlap only the upper surface of the wavelength conversion layer 50 and not overlap the side surface.

The intermodule coupling member 610 may include a polymer resin or an adhesive or adhesive tape.

In another embodiment, the intermodule coupling member 610 may further perform a light transmission blocking function. For example, the intermodule coupling member 610 may include a light absorbing material such as a black pigment, a dye, or the like, or may include a reflective material to perform a light transmission blocking function.

The display device 1000 may further include a housing 500. The housing 500 is open at one surface thereof and includes a bottom surface 510 and a sidewall 520 connected to the bottom surface 510. The light source 400, the optical member 100 / display panel 300 attachment body, and the reflective member 90 may be accommodated in a space defined by the bottom surface 510 and the sidewall 520. The light source 400, the reflective member 90, and the optical member 100 / display panel 300 attachment are disposed on the bottom surface 510 of the housing 500. The height of the sidewall 520 of the housing 500 may be substantially the same as the height of the attachment of the optical member 100 / display panel 300 placed inside the housing 500. The display panel 300 is disposed adjacent to the top of the sidewall of the housing 500, and they may be coupled to each other by the housing coupling member 620. The housing coupling member 620 may have a planar rectangular frame shape. The housing coupling member 620 may include a polymer resin or an adhesive or adhesive tape.

The display device 1000 may further include at least one optical film 200. One or more optical films 200 may be accommodated in a space surrounded by the intermodule coupling member 610 between the optical member 100 and the display panel 300. Sides of one or the plurality of optical films 200 may be attached to and in contact with the inner surface of the inter-module coupling member 610. In the drawings, a case in which the optical film 200 and the optical member 100 and the optical film 200 and the display panel 300 are spaced apart from each other is illustrated. However, the space is not necessarily required.

The optical film 200 may be a prism film, a diffusion film, a micro lens film, a lenticular film, a polarizing film, a reflective polarizing film, a retardation film, or the like. The display device 1000 may include a plurality of optical films 200 of the same type or different types. When a plurality of optical films 200 are applied, each optical film 200 is disposed to overlap each other, each side may be in contact with the inner surface of the inter-module coupling member 610 and attached thereto. The optical films 200 may be spaced apart from each other, and an air layer may be disposed therebetween.

The display device 1000 according to the exemplary embodiment of FIG. 24 integrates the optical member 100, the display panel 300, and even the optical film 200 through the intermodule coupling member 610, and the housing coupling member 620. The display panel 300 and the housing 500 are coupled to each other. Therefore, even if the mold frame is omitted, the various members can be stably coupled, thereby making it possible to reduce the weight of the display device 1000. In addition, the light guide plate 10 and the wavelength conversion layer 50 are integrated to reduce the thickness of the display device 1000. In addition, the side of the display panel 300 and the sidewall 520 of the housing 500 may be coupled to each other by the housing coupling member 620 to eliminate or minimize the display screen side bezel space.

25 is a cross-sectional view of a display device according to another exemplary embodiment.

Referring to FIG. 25, the display device 1000_1 includes a light source 400, an optical member 100_1 disposed on an emission path of a light source, and a display panel 300 disposed above the optical member. FIG. 25 illustrates a display device 1001 including an optical member 100_1 covering a top surface and a side surface of a wavelength conversion layer 50_1 and a side surface of the wavelength conversion lower layer 70_1, unlike in FIG. 24. do.

The wavelength conversion layer 50_1, in particular the wavelength conversion particles contained therein, is vulnerable to moisture / oxygen. In the case of the wavelength conversion film, a barrier film is stacked on the upper and lower surfaces of the wavelength conversion layer to prevent moisture / oxygen penetration into the wavelength conversion layer. However, in the present embodiment, the wavelength conversion layer 50_1 is directly disposed without the barrier film. A sealing structure for protecting the wavelength conversion layer 50_1 is required. The sealing structure may be implemented by the wavelength conversion upper layer 60_1 and the light guide plate 10_1.

Gates through which moisture can penetrate into the wavelength conversion layer 50_1 are the top, side, and bottom surfaces of the wavelength conversion layer 50_1. As described above, the upper and side surfaces of the wavelength conversion layer 50_1 are covered and protected by the wavelength conversion upper layer 60_1, so that moisture / oxygen penetration may be blocked or at least reduced (hereinafter referred to as 'blocking / reducing').

On the other hand, the lower surface of the wavelength conversion layer 50_1 is in contact with the upper surface of the wavelength conversion lower layer 70_1. When the wavelength conversion lower layer 70_1 includes voids VD or is made of an organic material, the inside of the wavelength conversion lower layer 70_1 Moisture can be moved in, so that the water / oxygen can penetrate through the wavelength conversion layer 50_1 through it. However, in the present exemplary embodiment, since the wavelength conversion lower layer 70_1 has a sealing structure, it may be fundamentally blocked from moisture / oxygen penetration through the lower surface of the wavelength conversion layer 50_1.

Specifically, since the side surface of the wavelength conversion lower layer 70_1 is covered and protected by the wavelength conversion upper layer 60_1, moisture / oxygen penetration through the side surface of the wavelength conversion lower layer 70_1 may be blocked / reduced. Even when the wavelength conversion lower layer 70_1 protrudes from the wavelength conversion layer 50_1 and a part of the upper surface is exposed, the portion is covered and protected by the wavelength conversion upper layer 60_1, so that the moisture / oxygen penetration may also be blocked / reduced. The lower surface of the wavelength conversion lower layer 70_1 is in contact with the light guide plate 10_1. When the light guide plate 10_1 is formed of an inorganic material such as glass, the light guide plate 10_1 may block / reduce moisture / oxygen penetration like the wavelength conversion upper layer 60_1. As a result, the laminate of the wavelength converting underlayer 70_1 and the wavelength converting layer 50_1 is sealed while the surface is surrounded by the wavelength converting upper layer 60_1 and the light guide plate 10_1, although the moisture / oxygen inside the wavelength converting underlayer 70_1 is sealed. Even if a movement path is provided, moisture / oxygen permeation itself can be blocked / reduced by the sealing structure, thereby preventing or at least mitigating degradation of the wavelength conversion particles by moisture / oxygen.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. I can understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

10: Light guide plate
20: low refractive bottom layer
30: low refractive layer
40: low refractive top layer
50: wavelength conversion layer
60: wavelength converting top layer
70: wavelength conversion bottom layer
80: scattering pattern
90: reflective member
100: optical member
400: light source

Claims (61)

Light guide plate;
A low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate;
A low refractive index lower layer disposed between the low refractive index layer and the light guide plate and having a thickness smaller than that of the low refractive index layer; And
An optical member comprising a wavelength conversion layer disposed on the low refractive index layer. According to claim 1,
And a lower surface of the low refractive index lower layer contacting an upper surface of the light guide plate, and an upper surface of the low refractive index lower layer contacting a lower surface of the low refractive index layer. The method of claim 2,
The low refractive index lower layer may include a low refractive material having a refractive index of 1.3 to 1.7 or a high refractive material having a refractive index of 1.5 to 2.2. The method of claim 3, wherein
The refractive index of the low refractive index lower layer is greater than the refractive index of the low refractive index layer. The method of claim 4, wherein
The low refractive index lower layer includes a first low refractive index lower layer disposed on the light guide plate and a second low refractive index lower layer disposed on the first low refractive index lower layer. The method of claim 5,
Any one of the first low refractive index lower layer and the second low refractive index lower layer includes the low refractive material, and the other includes the high refractive material. The method of claim 6,
The thickness of the first low refractive index lower layer and the thickness of the second low refractive index lower layer are each 0.2um or less. The method of claim 6,
The low refractive material is SiOx, and the high refractive material is SiNx. According to claim 1,
An optical member having a difference in refractive index between the light guide plate and the low refractive index layer is 0.2 or more. The method of claim 9,
The low refractive index layer comprises a void. The method of claim 9,
The refractive index of the low refractive index layer is 1.2 to 1.3 optical member. The method of claim 11, wherein
The thickness of the low refractive layer is 0.8um to 1.2um optical member. According to claim 1,
And a wavelength converting upper layer disposed on the wavelength converting layer. The method of claim 13,
The lower surface of the wavelength conversion upper layer is parallel to the upper surface of the light guide plate. The method of claim 14,
The wavelength conversion top layer comprises SiOx or SiNx. The method of claim 15,
The wavelength conversion top layer includes a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer. The method of claim 16,
One of the first wavelength converting top layer and the second wavelength converting top layer comprises a transparent organic material, and the other includes any one of SiOx and SiNx. The method of claim 17,
Wherein the first wavelength converting top layer comprises SiOx and the second wavelength converting top layer comprises a transparent organic material. The method of claim 16,
One of the first wavelength converting top layer and the second wavelength converting top layer comprises SiOx and the other comprises SiNx. The method of claim 16,
The wavelength conversion top layer further comprises a third wavelength conversion top layer on the second wavelength conversion top layer. The method of claim 20,
And the first wavelength converting upper layer comprises a transparent organic material. The method of claim 21,
One of the second wavelength converting top layer and the third wavelength converting top layer comprises SiOx and the other comprises SiNx. According to claim 1,
The light guide plate comprises a glass. The method of claim 23, wherein
The upper surface of the light guide plate is parallel to the lower surface of the low refractive layer. Light guide plate;
A low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate;
A wavelength conversion layer disposed on the low refractive layer; And
And a low refractive upper layer disposed on the low refractive layer and the wavelength conversion layer and having a thickness smaller than that of the low refractive layer. The method of claim 25,
The low refractive upper layer may include a low refractive material having a refractive index of 1.3 to 1.7 or a high refractive material having a refractive index of 1.5 to 2.2. The method of claim 26,
The refractive index of the low refractive upper layer is greater than the refractive index of the low refractive layer. The method of claim 27,
The low refractive upper layer includes a first low refractive upper layer disposed on the low refractive layer and a second low refractive upper layer disposed on the first low refractive upper layer. The method of claim 28,
One of the first low refractive index upper layer and the second low refractive index upper layer includes the low refractive material, and the other includes the high refractive material. The method of claim 29,
The thickness of the first low refractive index upper layer and the thickness of the second low refractive index upper layer are each 0.2um or less. The method of claim 30,
The low refractive material is SiOx, and the high refractive material is SiNx. The method of claim 25,
And a wavelength converting upper layer disposed on the wavelength converting layer. 33. The method of claim 32,
The wavelength conversion top layer comprises SiOx or SiNx. The method of claim 33, wherein
The wavelength conversion top layer includes a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer. The method of claim 34, wherein
One of the first wavelength converting top layer and the second wavelength converting top layer comprises a transparent organic material, and the other includes any one of SiOx and SiNx. 36. The method of claim 35 wherein
Wherein the first wavelength converting top layer comprises SiOx and the second wavelength converting top layer comprises a transparent organic material. The method of claim 34, wherein
The wavelength conversion top layer further comprises a third wavelength conversion top layer on the second wavelength conversion top layer. Light guide plate;
A low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate;
A wavelength conversion layer disposed on the low refractive layer;
A low refractive index lower layer disposed between the low refractive index layer and the light guide plate; And
And a low refractive upper layer disposed on the low refractive layer and the wavelength conversion layer. The method of claim 38, wherein
The low refractive index lower layer includes SiOx or SiNx, and the refractive index of the low refractive index lower layer is greater than the refractive index of the low refractive index layer. The method of claim 39,
The low refractive index lower layer includes a first low refractive index lower layer disposed on the light guide plate and a second low refractive index lower layer disposed on the first low refractive index lower layer. 41. The method of claim 40 wherein
The thickness of the first low refractive index lower layer and the thickness of the second low refractive index lower layer are each 0.2um or less. The method of claim 38, wherein
The low refractive upper layer comprises SiOx or SiNx, the refractive index of the low refractive upper layer is greater than the refractive index of the low refractive layer. The method of claim 42, wherein
The low refractive upper layer includes a first low refractive upper layer disposed on the low refractive layer and a second low refractive upper layer disposed on the first low refractive upper layer. The method of claim 43,
The thickness of the first low refractive index upper layer and the thickness of the second low refractive index upper layer are each 0.2um or less. The method of claim 38, wherein
And a wavelength converting upper layer disposed over the wavelength converting layer, wherein the wavelength converting upper layer comprises SiOx or SiNx. 46. The method of claim 45,
The wavelength conversion top layer includes a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer. 47. The method of claim 46 wherein
One of the first wavelength converting top layer and the second wavelength converting top layer comprises a transparent organic material, and the other includes any one of SiOx and SiNx. The method of claim 47,
Wherein the first wavelength converting top layer comprises SiOx and the second wavelength converting top layer comprises a transparent organic material. 47. The method of claim 46 wherein
The wavelength conversion top layer further comprises a third wavelength conversion top layer on the second wavelength conversion top layer. Light Guide Plate,
A low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate,
A low refractive index lower layer disposed between the low refractive index layer and the light guide plate, and
An optical member including a wavelength conversion layer disposed on the low refractive layer;
A light source disposed on at least one side of the light guide plate; And
And a display panel disposed above the optical member. 51. The method of claim 50,
The low refractive index lower layer includes SiOx or SiNx, and the refractive index of the low refractive index lower layer is greater than the refractive index of the low refractive index layer. The method of claim 51, wherein
The low refractive index lower layer includes a first low refractive index lower layer disposed on the light guide plate and a second low refractive index lower layer disposed on the first low refractive index lower layer. 51. The method of claim 50,
And a wavelength conversion upper layer disposed on the wavelength conversion layer, wherein the wavelength conversion upper layer comprises SiOx or SiNx. The method of claim 53,
The wavelength conversion top layer includes a first wavelength conversion top layer disposed on the wavelength conversion layer and a second wavelength conversion top layer disposed on the first wavelength conversion top layer. 55. The method of claim 54,
The wavelength conversion top layer further includes a third wavelength conversion top layer on the second wavelength conversion top layer. 51. The method of claim 50,
The optical member further includes a low refractive index upper layer disposed between the wavelength conversion layer and the low refractive index layer. The method of claim 56, wherein
The low refractive upper layer includes SiOx or SiNx, and the refractive index of the low refractive upper layer is greater than the refractive index of the low refractive layer. The method of claim 57,
And a wavelength conversion upper layer disposed on the wavelength conversion layer, wherein the wavelength conversion upper layer comprises SiOx or SiNx. Light Guide Plate,
A low refractive layer disposed on the light guide plate and having a refractive index smaller than that of the light guide plate,
A wavelength conversion layer disposed on the low refractive layer, and
An optical member including a low refractive upper layer disposed between the low refractive layer and the wavelength conversion layer;
A light source disposed on at least one side of the light guide plate; And
And a display panel disposed above the optical member. The method of claim 59,
The low refractive upper layer includes SiOx or SiNx, and the refractive index of the low refractive upper layer is greater than the refractive index of the low refractive layer. 61. The method of claim 60,
And a wavelength conversion upper layer disposed on the wavelength conversion layer, wherein the wavelength conversion upper layer comprises SiOx or SiNx.

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